Urbain Jean Joseph Le Verrier (11 March 1811 – 23 September 1877) was a French
mathematicianA mathematician is a person whose primary area of study and/or research is the field of mathematics. Mathematicians are concerned with particular problems related to logic, space, transformations, numbers and more general ideas which encompass these concepts...
who specialized in
celestial mechanicsCelestial mechanics is the branch of astronomy that deals with the motions of celestial objects. The field applies principles of physics, historically classical mechanics, to astronomical objects such as stars and planets to produce ephemeris data. Orbital mechanics is a subfield which focuses on...
and is best known for his part in the discovery of
NeptuneNeptune is the eighth planet from the Sun in our Solar System. Named for the Roman god of the sea, it is the fourth-largest planet by diameter and the third-largest by mass. Neptune is 17 times the mass of Earth and is slightly more massive than its near-twin Uranus, which is 15 Earth masses and...
.
Le Verrier was born in
Saint-LôSaint-Lô is a commune in north-western France, the capital of the Manche department in Normandy.-History:Originally called Briovère , the town is built on and around ramparts. Originally it was a Gaul fortified settlement...
, France, and studied at the Ecole Polytechnique. Following a brief period studying chemistry under Gay-Lussac, Le Verrier switched to astronomy, particularly celestial mechanics.
Urbain Jean Joseph Le Verrier (11 March 1811 – 23 September 1877) was a French
mathematicianA mathematician is a person whose primary area of study and/or research is the field of mathematics. Mathematicians are concerned with particular problems related to logic, space, transformations, numbers and more general ideas which encompass these concepts...
who specialized in
celestial mechanicsCelestial mechanics is the branch of astronomy that deals with the motions of celestial objects. The field applies principles of physics, historically classical mechanics, to astronomical objects such as stars and planets to produce ephemeris data. Orbital mechanics is a subfield which focuses on...
and is best known for his part in the discovery of
NeptuneNeptune is the eighth planet from the Sun in our Solar System. Named for the Roman god of the sea, it is the fourth-largest planet by diameter and the third-largest by mass. Neptune is 17 times the mass of Earth and is slightly more massive than its near-twin Uranus, which is 15 Earth masses and...
.
Early life and career
Le Verrier was born in
Saint-LôSaint-Lô is a commune in north-western France, the capital of the Manche department in Normandy.-History:Originally called Briovère , the town is built on and around ramparts. Originally it was a Gaul fortified settlement...
, France, and studied at the Ecole Polytechnique. Following a brief period studying chemistry under Gay-Lussac, Le Verrier switched to astronomy, particularly celestial mechanics. He accepted a job at the
Paris ObservatoryThe Paris Observatory is the foremost astronomical observatory of France, and one of the largest astronomical centers in the world.-Constitution:...
, where he spent most of his professional life, and eventually became that institution's Director. In 1855, he was elected a foreign member of the
Royal Swedish Academy of SciencesThe Royal Swedish Academy of Sciences or Kungliga Vetenskapsakademin is one of the Royal Academies of Sweden. The Academy is an independent, non-governmental scientific organization which acts to promote the sciences, primarily the natural sciences and mathematics.The Academy was founded on 2 June...
.
Discovery of Neptune
Le Verrier's most famous achievement is his prediction of the existence of the then unknown planet Neptune, using only
mathematicsMathematics is the science and study of quantity, structure, space, and change. Mathematicians seek out patterns, formulate new conjectures, and establish truth by rigorous deduction from appropriately chosen axioms and definitions....
and astronomical observations of the known planet Uranus. Encouraged by physicist
AragoFrançois Jean Dominique Arago was a French Catalan mathematician, physicist, astronomer and politician.-Early life and work:...
,, Director of the Paris Observatory, Le Verrier was intensely engaged for months in complex calculations to explain small but systematic discrepancies between
UranusUranus is the seventh planet from the Sun, and the third-largest and fourth most massive planet in the Solar System. It is named after the ancient Greek deity of the sky Uranus the father of Kronos and grandfather of Zeus...
's observed
orbitIn physics, an orbit is the gravitationally curved path of one object around a point or another body, for example the gravitational orbit of a planet around a star....
and the one predicted from the
lawsA physical law or scientific law is a scientific generalization based on empirical observations of physical behavior . Laws of nature are observable. Scientific laws are empirical, describing the observable laws...
of gravity of
NewtonSir Isaac Newton FRS was an English physicist, mathematician, astronomer, natural philosopher, alchemist, and theologian who is perceived and considered by a substantial number of scholars and the general public as one of the most influential men in history...
. At the same time, but unknown to Le Verrier, similar calculations were made by
John Couch AdamsJohn Couch Adams was a British mathematician and astronomer. Adams was born in Laneast, near Launceston, Cornwall and died in Cambridge. The Cornish name Couch is pronounced "cooch"....
in England. Le Verrier announced his final predicted position for Uranus's unseen perturbing
planetA planet , is a celestial body orbiting a star or stellar remnant that is massive enough to be rounded by its own gravity, is not massive enough to cause thermonuclear fusion, and has cleared its neighbouring region of planetesimals.The term planet is ancient, with ties to history, science,...
publicly to the French Academy on 31 August 1846, two days before Adams's final solution, which turned out to be 12° off the mark, was privately mailed to the Royal Greenwich Observatory. Le Verrier transmitted his own prediction by 18 September letter to
Johann GalleJohann Gottfried Galle was a German astronomer at the Berlin Observatory who, with the assistance of student Heinrich Louis d'Arrest, was the first person to view the planet Neptune, and know what he was looking at...
of the
Berlin ObservatoryThe Berlin Observatory has its origins in 1700 when Gottfried Leibniz initiated the Societät der Wissenschaften which would later become the Preußischen Akademie der Wissenschaften...
. The letter arrived five days later, and the planet was found with the Berlin Fraunhofer refractor that same evening, 23 September 1846, by Galle and Heinrich d'Arrest within 1° of the predicted location near the boundary between Capricorn and
AquariusAquarius is a constellation of the zodiac, situated between Capricornus and Pisces. Its name is Latin for "water-bearer" or "cup-bearer", and its symbol is , a representation of water....
.
There was, and to an extent still is, controversy over the apportionment of credit for the discovery. There is no ambiguity to the discovery claims of Le Verrier, Galle, and d'Arrest. Adams's work was begun earlier than Le Verrier's but was finished later and was unrelated to the actual discovery. Not even the briefest account of Adams's predicted orbital elements was published until more than a month after Berlin's visual confirmation. But Adams himself made full public acknowledgement of Le Verrier's priority and credit (not forgetting to mention the role of Galle) when he gave his paper to the Royal Astronomical Society in November 1846:
Scholars' opinion has been moving in recent years to a view that Le Verrier's open prediscovery publication of his predictions merits his credit, heretofore too long denied, as sole mathematical discoverer of Neptune.
Later life and legacy
Galvanized by his success with Neptune, Le Verrier proceeded to interpret variations in the orbit of
MercuryFor the liquid metallic element, see Mercury .Mercury is the innermost and smallest planet in the Solar System, orbiting the Sun once every 87.969 days. The orbit of Mercury has the highest eccentricity of all the Solar System planets, and it has the smallest axial tilt. It completes three...
as being due to an unknown planet, tentatively named Vulcan. This triggered a wave of false detections, which lasted until 1915, when
EinsteinAlbert Einstein was a theoretical physicist. His many contributions to physics include the special and general theories of relativity, the founding of relativistic cosmology, the first post-Newtonian expansion, explaining the perihelion advance of Mercury, prediction of the deflection of...
explained Mercury's anomalous motion with his theory of general relativity.
The last quarter century of Le Verrier's life was engaged in establishing the orbits of all eight planets, a project which he only narrowly lived to see completed and printed.
Le Verrier had a wife and children. He died in
ParisParis is the capital of France and the country's most populous city. It is situated on the river Seine, in northern France, at the heart of the Île-de-France region...
,
FranceFrance , officially the French Republic , is a country located in Western Europe, with several overseas islands and territories located on other continents. Metropolitan France extends from the Mediterranean Sea to the English Channel and the North Sea, and from the Rhine to the Atlantic Ocean...
and was buried in the Cimetière Montparnasse. A large stone celestial globe sits over his grave. He will be remembered by the phrase attributed to Arago: "the man who discovered a planet with the point of his pen."
Honours
- Gold Medal of the Royal Astronomical Society
The Gold Medal is the highest award of the Royal Astronomical Society.-History:In the early years, more than one medal was often awarded in a year, but by 1833 only one medal was being awarded per year. This caused a problem when Neptune was discovered in 1846, because many felt an award should...
- 1868 and 1876
- Namesake of crater
In the broadest sense, the term impact crater can be applied to any depression, natural or manmade, resulting from the high velocity impact of a projectile with a larger body...
s on the MoonLe Verrier is a small lunar impact crater located in the northern part of the Mare Imbrium. To the west is the slightly larger crater Helicon, and farther to the west-northwest lies the mountain-ringed bay Sinus Iridum....
and MarsMars is the fourth planet from the Sun in the Solar System. The planet is named after Mars, the Roman god of war. It is also referred to as the "Red Planet" because of its reddish appearance, due to iron oxide prevalent on its surface....
, a ring of NeptuneThe rings of Neptune were discovered in 1989 by the Voyager 2 spacecraft and are tenuous, faint and dusty, and resemble the rings of Jupiter more closely than those of Saturn or Uranus. Neptune possesses five known rings, each named for an astronomer who contributed important work on the planet:...
, and the asteroidthumb|260px|right|[[253 Mathilde]], a [[C-type asteroid]] measuring about across. Photograph taken in 1997 by the [[NEAR Shoemaker]] probe.Asteroids, sometimes called minor planets or planetoids, are small Solar System bodies in orbit around the Sun, especially in the inner Solar System; they are...
1997 Leverrier1997 Leverrier is a main belt asteroid. It was discovered by the Indiana Asteroid Program and was named after Urbain Le Verrier, the French mathematician who, simultaneously with John Couch Adams, predicted the existence and position of the planet Neptune....
- One of the 72 names engraved on the Eiffel Tower
On the Eiffel Tower, seventy-two names of French scientists, engineers and some other notable people are engraved in recognition of their contributions by Gustave Eiffel. The engravings are found on the sides of the tower under the first balcony...
Further reading
- Le Verrier, Urbain (1835). Annales de Chimie et de Physique
Annales de chimie et de physique is a scientific journal that was founded in Paris, France, in 1789 under the title Annales de chimie. One of the early editors was the French chemist Antoine Lavoisier. In 1815, it became the Annales de chimie et de physique, and was published under that name for...
(Paris) 60: 174 - Chemical research of Le Verrier
- Fabien Locher, Le Savant et la Tempête. Étudier l’atmosphère et prévoir le temps au XIXe siècle, Rennes, Presses Universitaires de Rennes, Collection « Carnot », 2008.
- Dennis Rawlins
Dennis Rawlins is an American astronomer, historian, and publisher.-Polar controversies:While studying historical magnetic declination data in polar regions, Rawlins was surprised to find that there were no such data from the 1909 expedition of Robert E...
(1999). Recovery of the RGO Neptune Papers. Adams' Final Prediction Missed by Over Ten Degrees. DIO, volume 9, number 1, pages 3–25.
tja !
External links